Up until this day, there is no other option available for drug disposal besides discarding as household trash, flushing down to the toilet, or throwing out in an incinerator.  Drug recycle may be a better solution than disposal.  Recycling drugs will turn them into a new product, which will eliminate the concern of environmental pollution caused by drug disposal. In the drug recycle concept, the active pharmaceutical ingredient (API) is recovered from unused tablets or capsule by solid-liquid extraction, followed by crystallization to retrieve the extracted API back in the solid form.  This concept has been tested in the recovery of three class of drugs: ibuprofen (non-steroidal anti-inflammatory drug/NSAID), acetaminophen (common painkiller), and tetracycline HCl (antibiotic).  Using this technique, about 60-80% of the APIs could be recovered from the tablets/capsules.  More importantly, the recovered APIs have the qualities acceptable for drug use according to HPLC assay measurement.

The drug recycle technique based on solid-liquid extraction and crystallization has been successfully implemented to recover an API from many different brands all at once, using ibuprofen, acetaminophen, and tetracycline HCl as case examples.  The amount of API that could be recovered was about 60-80% from the original amount written in the label.  The quality of the recovered APIs was measured by HPLC assay, in which 99.7%, 99.1%, and 99.2% assay was successfully reached for ibuprofen, acetaminophen, and tetracycline HCl, respectively.

The recycle process consists of solid-liquid extraction and crystallization, which are common industrial unit operations.  Only stirred-tank vessel, filtration, and drying equipment are required.  The recycling process can even be performed for drug products from different manufacturers, as long as the API is the same.  Because of its simplicity and robustness, scale-up should be straightforward.